Country
Portugal
City / Region
Oeiras / Lisboa
Construction Date
Started in 1553, during the second half of the 16th century (reign of D. João III), with significant modifications in the 17th and 18th centuries.
Conservation status
Classified as Property of Public Interest (IIP) in July 1957. Currently under the responsibility of the Ministério da Defesa Nacional, it is used for representational acts of Defense organizations. It is in good general condition, having undergone various conservation and remodeling interventions over the years. Its trajectory, from a key fortress to a prison, followed by formal military decommissioning (1947) and re-functionalization for state representational acts, illustrates the common path of large fortifications that lose their primary military function but maintain a strong symbolic and heritage value for the State.
Latitude and Longitude
38°40'27"N 9°19'30"W
Main characteristics
Considered the largest and most complete Vauban-style military defense complex remaining in Portugal. It has an excellent strategic position at the mouth of the Tagus River, cross-firing with Forte de São Lourenço do Bugio. The plan is almost pentagonal, protected on land by two moats and, originally, by a drawbridge. It features a complex defensive system with a ravelin, powerful bastions (such as Príncipe/D. Fernando and Santo António), terraced battery esplanades, sentry boxes, etc. Internally, it included a chapel, vaulted casemates, and a notable vaulted cistern with three naves on Tuscan columns. It was one of the first bastioned fortifications in Portugal. The description as "Vauban style," despite being initiated much earlier (1553 vs. Vauban active in the 2nd half of the 17th century), suggests that later modifications incorporated principles associated with the French school of fortification (complexity of bastions, outer works, elaborate moats), superimposing them on the initial Renaissance structure and resulting in an architectural palimpsest representative of the evolution of military engineering. Historically, it functioned not only as the "Shield of the Kingdom" but also as a state prison (where General Gomes Freire de Andrade was detained) and the place of origin of the Colégio Militar. In the early 20th century, it had an internal railway line for transporting ammunition.
Source(s)
AAVV. À Descoberta das Sentinelas - Roteiro das Fortalezas da Região de Lisboa e Vale do Tejo. Lisboa: Associação de Turismo de Lisboa, 1998.
AZEVEDO, Carlos de; FERRÃO, Julieta; GUSMÃO, Adriano de. Monumentos e Edifícios Notáveis do Distrito de Lisboa. Lisboa: [s.n.], 1963. t. 2 e 3. BARBOSA, I. Vilhena. Archivo Pittoresco. Lisboa: Tipografia de Castro & Irmão, 1863. v. 6.
CALLIXTO, Carlos Pereira. Fortificações Marítimas do Concelho de Oeiras. Oeiras: Câmara Municipal de Oeiras, [s.d.].
CALLIXTO, Carlos Pereira. Resumo Histórico da Torre ou Fortaleza de São Julião da Barra. Lisboa: [s.n.], 1980.
COSTA GUEDES, Lívido da. O Arco de Belém - S. Julião da Barra contorno da Anseada de Paço de Arcos. Lisboa: [s.n.], 1986.
GIL, Júlio; CABRITA, Augusto. Os mais belos castelos e fortalezas de Portugal. Lisboa: Verbo, 1986.
LOURENÇO, Manuel Acácio Pereira. As Fortalezas da Costa Marítima de Cascais. Cascais: Câmara Municipal de Cascais, 1964.
MOREIRA, Rafael. "A Arquitectura Militar". In: História da Arte em Portugal. Lisboa: Publicações Alfa, 1986. v. 7.
PORTUGAL. Direção-Geral dos Edifícios e Monumentos Nacionais (DGEMN). Monumentos. Lisboa: DGEMN, n. 7, 16-21, 1997, 2002-2004.
PORTUGAL. Ministério da Defesa Nacional. Forte de São Julião da Barra. [Online]. Disponível em: https://www.defesa.gov.pt/pt/adefesaeeu/fsjb. Acesso em: [Data de acesso].
RIBEIRO, Aquilino. Oeiras.: [s.n.], 1940.
ROCHA, Filomena. Oeiras, o Património - a História. Oeiras: Câmara Municipal de Oeiras, 1997.
VITERBO, Sousa. Diccionario Historico e Documental dos Architectos, Engenheiros e Construtores Portuguezes ou a serviço de Portugal. Lisboa: Imprensa Nacional, 1904. v. 2.